by Pablo Päster under AskPablo of TreeHugger on Sun 7 Aug 2011
Image credit: Karen, used under Creative Commons license.
Dear Pablo: Say an average fancy t-shirt holds carbon footprint of 6kg but is never sold and sits in the warehouse of a textile/clothing production company. I take that same t-shirt and use it to make a new one. Does the new product inherit the same carbon footprint or is it less because I am repurposing it?
Questions such as this are an important part of Life Cycle Assessment (LCA). LCA has several standards associated with it, including ISO 14040:2006 (Life Cycle Assessment: Principles and Framework), ISO 14044:2006 (Life Cycle Assessment: Requirements and Guidelines), PAS 2050, and the new GHG Protocol Product Standard, but none of them are prescriptive enough to provide a clear answer. For example, the LCA practitioner has a lot of flexibility around defining boundaries and other variables so that two LCA studies of the same apple could yield different results. The value of LCA is that a clearly documented quantification process should produce repeatable and consistent results so that two apples could be compared. When the answer is not clearly given in the standards, we must rely on the guiding principles behind them; Relevance, Completeness, Consistency, Transparency and Accuracy…. Read the full story on TreeHugger